Technical Specifications

P. 31
Allowable Roof Uniform Load Capacities (continued)
TABLE 18
–
LDF = 1.15
P3 Joist — PJI 90 without Web Stiffeners
Allowable uniform loads (PLF) Roof
Clear
Joist
Span
(ft�)
11-7/8” 14” 16”
Live
Load
Total
Load
Live
Load
Total
Load
Live
Load
Total
Load
Defl�
L/240
Snow
115%
Non-
Snow
125%
Defl�
L/240
Snow
115%
Non-
Snow
125%
Defl�
L/240
Snow
115%
Non-
Snow
125%
14 181 197 198 216 210 229
15 169 184 185 201 196 213
16 159 173 174 189 184 200
17 149 162 163 178 173 188
18 141 153 154 168 164 178
19 134 145 146 159 155 168
20 127 138 139 151 147 160
21 121 131 132 144 140 152
22 115 125 126 137 134 145
23 110 120 121 131 128 139
24 104 106 115 116 126 123 133
25 92 102 110 111 121 118 128
26 81 98 106 107 116 113 123
27 73 94 97 103 112 109 119
28 65 87 87 95 99 108 105 114
29 59 78 78 85 96 104 102 110
30 53 71 71 77 93 101 98 107
31 48 64 64 70 90 93 94 95 103
32 44 58 58 63 85 85 86 92 100
33 40 53 53 58 77 77 78 89 97
34 36 49 49 53 70 70 71 87 94
35 33 45 45 48 65 65 65 84 87
36 31 41 41 45 59 59 60 80 80
37 28 38 38 41 55 55 55 74 74
38 26 35 35 38 50 50 51 68 68
39 24 32 32 35 47 47 47 63 63
40 22 30 30 32 43 43 44 58 58
NOTES
1� Roof joists or rafters must be sloped
a minimum of 1/4” in 12”�
2� Live Load column limits deflection
to L/240; Total Load column limits def-
lection to L/180� Cathedral ceilings or
sheet rocked rafters may require stiffer
performance or additional design�
3� Values represent the most restric-
tive of simple span or multiple span
conditions�
4� Values are for P3 Joist spaced at a
maximum of 24” on center�
5� Table assumes a minimum end bearing
length of 1-3/4” and a minimum interior
bearing length of 3-1/2”�
6� Web stiffeners are not required
except when the joist hangers do not
pro videlateral support for the top flange
of the P3 Joist� Web stiffeners are
required at birdsmouth cuts and when
required by hanger manufacturers for
properconnections�
JOIST SIZING
1� Select desired joist depth (column)�
2� Select desired span (row)�
3� Check BOTH Live Load and Total Load
columns�
4� If Live Load column is blank, Total Load
capacity governs�